Motivated light

Light the scene can explain: every glow traceable to a window, lamp or fire, even when hidden units do the real work.

Motivated lighting is realism's accounting: the audience never asks where light comes from as long as an answer exists in the world, the window's day, the lamp's pool, the screen's flicker. The hidden rig may quadruple the practical's output, but it obeys the practical's direction and colour, so the fiction stays solvent.

Unmotivated light is a style in itself, theatre and myth glow from nowhere gladly, but mixing regimes is what breaks belief: one sourceless slash in a naturalistic scene reads as error. Our imagery holds the discipline strictly: the gold always has a source, a mote, a fire, a lamp, because light with a reason is light with a story.